[zapita]

> builds are performed "inside out"

Docker supports multi-stage builds. They are quite powerful and allow you go beyond the "inside out" model (which still works fine for many use cases).

> ...and aren't reproducible

You can have reproducible builds with Docker. But Docker does not require your build to be reproducible. This allowed it to be widely adopted, because it meets users where they are. You can switch your imperfect build to Docker now, and gradually improve it over time.

This is a pragmatic approach which in the long run improves the state of the art more than a purist approach.